PRODUCTION OF AN INTEGRATED CIRCUIT INCLUDING ELECTRICAL CONTACT ON SiC

ABSTRACT

Production of an integrated circuit including an electrical contact on SiC is disclosed. One embodiment provides for production of an electrical contact on an SiC substrate, in which a conductive contact is produced on a boundary surface of the SiC substrate by irradiation and absorption of a laser pulse on an SiC substrate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This Utility patent application claims priority to German PatentApplication No. DE 10 2006 050 360.0 filed on Oct. 25, 2007, which isincorporated herein by reference.

BACKGROUND

A method is described for production of an electrical contact on SiC.

Silicon carbide (SiC) represents a highly promising semiconductormaterial, in one embodiment for power and very high frequencyelectronics, because of its excellent physical characteristics. It isdistinguished in comparison to silicon, which has become industriallyestablished as a semiconductor material, by an electrical breakdownfield strength that is approximately 10 times greater, as well as bandgap and thermal conductivity values that are about 3 times greater,therefore allowing particular advantages with respect to power losses,power density and thermal load capacity. During the development ofelectronic components composed of SiC substrates, such as SiC Schottkydiodes or SiC-MOSFETs (SiC Metal Oxide Semiconductor Field EffectTransistors), conductive contacts must be formed on the SiC substratesin order to make electrical contact with and to gain access tocomponents produced in these substrates. A contact-formation processcarried out by heat-treatment of the SiC substrate, for example an ovenprocess or an RTP (Rapid Thermal Processing) process results in atemperature budget which can lead to restrictions in the processintegration for formation of the semiconductor component, since theremay be further processes which are adversely influenced by such a hightemperature budget.

A production method for an electrical contact on an SiC substrate whichallows more process flexibility would be desirable.

For these and other reasons, there is a need for the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of embodiments and are incorporated in and constitute apart of this specification. The drawings illustrate embodiments andtogether with the description serve to explain principles ofembodiments. Other embodiments and many of the intended advantages ofembodiments will be readily appreciated as they become better understoodby reference to the following detailed description. The elements of thedrawings are not necessarily to scale relative to each other. Likereference numerals designate corresponding similar parts.

FIGS. 1A to 1C illustrate schematic cross-sectional views of an SiCsubstrate during the production of an electrical contact, according toone embodiment.

FIGS. 2A to 2C illustrate schematic cross-sectional views of an SiCsubstrate during the production of an electrical contact.

FIGS. 3A to 3C illustrate schematic cross-sectional views of an SiCsubstrate during the production of a semiconductor component accordingto a further embodiment.

FIGS. 4A to 4E illustrate schematic cross-sectional views of an SiCsubstrate during the production of a semiconductor component accordingto a further embodiment.

FIGS. 5A to 5C illustrate schematic cross-sectional views of an SiCsubstrate during the production of an integrated circuit including asemiconductor component according to a further embodiment.

FIG. 6 illustrates a schematic illustration of the local irradiation ofa metal layer with a laser pulse.

DETAILED DESCRIPTION

In the following Detailed Description, reference is made to theaccompanying drawings, which form a part hereof, and in which is shownby way of illustration specific embodiments in which the invention maybe practiced. In this regard, directional terminology, such as “top,”“bottom,” “front,” “back,” “leading,” “trailing,” etc., is used withreference to the orientation of the Figure(s) being described. Becausecomponents of embodiments can be positioned in a number of differentorientations, the directional terminology is used for purposes ofillustration and is in no way limiting. It is to be understood thatother embodiments may be utilized and structural or logical changes maybe made without departing from the scope of the present invention. Thefollowing detailed description, therefore, is not to be taken in alimiting sense, and the scope of the present invention is defined by theappended claims.

It is to be understood that the features of the various exemplaryembodiments described herein may be combined with each other, unlessspecifically noted otherwise.

The views illustrated in the following figures are intended toillustrate a number of embodiments, and are not illustrated to scale.Similar or corresponding elements in the cross-sectional views areprovided with the same reference symbols. The sequential processesillustrated in the figures in the form of schematic cross-sectionalviews may be preceded or followed by further processes. In the same way,further processes may be introduced between two process stages (forexample the process stages in FIGS. 1A and 1B) which are illustrated asbeing sequential.

One embodiment provides a method for production of an integrated circuitincluding an electrical contact on an SiC substrate having the featuresthat an SiC substrate is provided, a metal layer is formed on onesurface of the SiC substrate, and the metal layer is irradiated with alaser pulse such that a metal silicide is formed by thermal action on aboundary surface to the SiC substrate.

By way of example, the SiC substrate may be a preprocessed SiCsubstrate. Elements of a semiconductor component to be formed cantherefore have been produced in or else on the SiC substrate at thisstage, for example well zones formed within the SiC substrate. Thethermal formation of the metal silicide composed of the silicon of theSiC substrate and a metal element of the metal layer is created byabsorption of the laser pulse, thus resulting in a temperature increasewhich causes a reaction between silicon and the metal of the metallayer, to form the metal silicide. During this process, carbon deposits,which contribute to the formation of the conductive contact, can also beformed as a reaction product of the silicide formation, on the boundarysurface.

The use of the laser pulse to form the silicide results in local heatingassociated with very short process times, in the order of magnitude ofmicroseconds or less. The temperature budget causing the formation ofsilicide with the laser pulse is several orders of magnitude less thanthe temperature budget for RTP and oven processes. This allows one ormore advantages in terms of the formation of the conductive contact, aswill become evident from the following statements. The carbon depositsas described above are produced during the silicide formation, and areused to form the conductive contact. The carbon contributes to theformation of the conductive contact only on the boundary surface to theSiC substrate. As the temperature budget increases for the silicideformation or subsequent processes, this results in seed formation ofcarbon deposits beyond the boundary surface in a contact metal area. Thecarbon that is bonded there is worthless in terms of reducing thecontact resistance, and can lead to the creation of weak points and thusto detachment of the contact metal, which can adversely affect thesolder capabilities of chips resulting from the SiC substrate. In thiscontext, it is particularly advantageous for the temperature budget tobe as low as possible after formation of the electrical contact.

In a further embodiment, a layer containing silicon is formed on thesurface of the SiC substrate before the formation of the metal layers,and the metal layer is subsequently produced on the layer which containssilicon. By way of example, the layer which contains silicon may beformed exclusively or predominantly from layers formed from silicon,such as polycrystalline silicon, amorphous silicon or doped forms of it.The layer which contains silicon may likewise also be a connecting layersuch as a metal silicide in which silicon represents a connectioncomponent. The layer which contains silicon is particularly suitable forcontrolling the metal silicide formation on the boundary surface to theSiC substrate, as well as the carbon deposits.

According to a further embodiment, the wavelength of the laser pulse ischosen to be in a range from 100 nm to 1000 nm. Although the wavelengthis chosen taking into account further parameters, for example takinginto account the thickness of a layer structure on the SiC substrate,the pulse length and the pulse energy, the wavelength is chosen in oneembodiment with respect to the absorption characteristics of the layerstructure and of the SiC substrate, as well as the reflection andtransmission behavior of the multilayer system. By way of example, it ispossible to use an excimer laser with a wavelength of 307 nm.

In a further embodiment, the thickness of a layer structure formed onthe SiC surface for irradiation with the laser pulse is in the rangefrom 10 to 50 nm. The layer structure can therefore be formed not onlyfrom the metal layer on its own but also from the layer which containssilicon plus the metal layer. In a further embodiment, the thickness ofthe layer structure is chosen to be in the range from 15 to 20 nm.

In a further embodiment, the metal layer includes at least one of theelements nickel, molybdenum, cobalt and titanium. However, in additionto these metals, it is also possible to use further metals which form asuitable metal silicide.

A further embodiment provides a method for production of an electricalcontact on an SiC substrate having the features of the SiC substratebeing provided with an exposed SiC surface, the exposed SiC surfacebeing irradiated with a laser pulse such that the SiC substrate losessilicon by thermal action on the surface, and a carbon structureremaining, and a contact reinforcement structure being formed on thecarbon structure.

This embodiment allows the formation of a conductive contact on an SiCsurface without previous metallization. In this case, the energyintroduced from the laser pulse into the SiC substrate as a result ofthe absorption of the laser pulse leads to vaporization of silicon fromthe SiC crystal lattice. At high surface temperatures such as these ofup to more than 1400° C., silicon has a higher partial pressure thancarbon. A carbon structure which remains in this case has, for example,an sp2 bonding state, for the formation of conductive contacts, as aresult of the bonding conditions in the SiC. The contact reinforcementstructure formed on this can be used to provide conductivemetallization, which can be soldered, without any furtherheat-treatment. By way of example, a metal stack composed of Ti/Ni/Ti/Agcan be used as the contact reinforcement structure. Further metalindividual-layer or multilayer systems may, of course, be used as thecontact reinforcement structure.

In a further embodiment, the laser pulse is chosen to have a wavelengthin the range from 100 nm to 350 nm. A short laser wavelength such asthis leads to suitable absorption of the laser energy on the SiCsurface, that is to say where very high surface temperatures arerequired in order to remove the silicon from the SiC crystal lattice.

In a further embodiment, a pulse duration in the range from 20 ns to2000 ns is chosen. When shortening the pulse duration, care must betaken to ensure that vaporization of irradiated material, and thereforeundesirable contamination of the laser system, are avoided.

In a further embodiment, the pulse energy is chosen to be in the rangefrom 0.5 J/cm² to 8 J/cm². The pulse energy is chosen taking account ofthe material-specific absorption characteristics of the SiC substrateand of the layer structure formed on it, as well as the temperature tobe achieved. With regard to the above embodiments, on the one hand ametal-silicide formation temperature must be achieved on the boundarysurface towards the SiC substrate, or else a comparatively hightemperature must be achieved for vaporization of silicon from the SiCstructure in the surface area of the SiC substrate. According to afurther embodiment, the pulse energy is chosen to be in the range from 2J/cm² to 4 J/cm².

In a further embodiment, the electrical contact is formed on a frontface and/or rear face of the SiC substrate. A front-face contact may beformed before the formation of a rear-face contact, or vice versa.Further processes, for example for definition of a semiconductorcomponent in the SiC substrate, may be carried out before, between orafter these processes for formation of the electrical contacts.

A further embodiment provides a method for production of a semiconductorcomponent having the features of an SiC semiconductor substrate beingprovided and processes being carried out in order to produce thesemiconductor component, wherein the processes include production of anelectrical contact according to one of the embodiments described above.

The semiconductor component to be formed may, for example, be in theform of a component for high-power, high-temperature and high-frequencyapplications, for example an SiC Schottky diode, an SiC-MOSFET orSiC-JFET (Junction Field Effect Transistor). However, a large number offurther SiC semiconductor components can be produced in addition to thecomponent types mentioned by way of example, with each semiconductorcomponent type being distinguished by a sequence of characteristicprocesses. However, an electrical contact is formed with the aid of thelaser pulse method described above, at least on one surface of the SiCsemiconductor substrate.

According to one embodiment, the SiC substrate is thinned from the rearface before the formation of an electrical rear-face contact. Risk offracture of the SiC substrate can be avoided by defining the electricalrear-face contact with a low thermal budget by using the laser pulsemethod as described above, at the end of the process chain for formationof the semiconductor component. Owing to the comparatively low thermalbudget for the laser pulse method, and the process flexibility achievedin this way, it is possible to form the rear-face contact at the end ofthe entire process since processes carried out prior to this, forexample relating to edge passivation by polyimide or of a metal on thefront face, are not adversely affected owing to the restricted and localthermal budget in the laser pulse method. This embodiment thereforemakes it possible, in one embodiment, to carry out a thin wafer processfor vertical SiC components which require a conductive rear-facecontact. In the case of vertical components such as these, the substrateresistance contributes significantly to the total resistance,particularly for voltage classes below 1000 V. Reducing the substratethickness from about 350 μm as at present therefore makes it possible toproduce SiC components with better performance features. Reducing thesubstrate thickness to values of less than 150 μm leads to aconsiderable improvement in the electrical characteristics of thevertical SiC components.

In a further embodiment relating to the production of a semiconductorcomponent, the electrical contact is formed on the front face by localirradiation of the metal layer with the laser pulse. The metal layer onthe surface of the SiC substrate is accordingly only partially convertedto the metal silicide.

In order to achieve such local irradiation of the metal layer with thelaser pulse, it is possible to use one or a combination of the followingprocesses, of scanning of the SiC substrate, use of reticles in the beampath, use of reflector layers and/or use of contact masks.

According to one embodiment, the semiconductor component corresponds toa Schottky diode, and a rear-face contact is produced after formation ofa Schottky junction. Although the temperature budget of subsequentprocesses is restricted after the formation of the Schottky contact, inorder to avoid adverse affects on the Schottky contact, a rear-facecontact can be produced subsequently by use of the laser pulse method asdescribed in this document.

According to a further embodiment, the semiconductor componentcorresponds to a merged pn-Schottky diode. In this case, a Schottkymetal on a front face of the SiC substrate is irradiated locally withthe laser pulse in order to produce the electrical contact. This makesit possible on the one hand to produce areas with a conductivecharacter, and on the other hand further areas with Schottkycharacteristics, with only one metallization process on the front face.This embodiment is therefore advantageous in comparison to a methodincluding the processes of metallization, local lift-off, annealing andrenewed metallization.

FIG. 1A illustrates a schematic cross-sectional view of an SiC substrate1 at the start of the process of forming an electrical contact,according to one embodiment. A layer containing silicon is applied tothe SiC substrate 1 and is used to control subsequent silicideformation. The layer which contains silicon may, for example, be formedfrom polycrystalline or amorphous silicon, or else from compoundscontaining silicon. A metal layer 3 is applied to the layer 2 whichcontains silicon. By way of example, the metal layer 3 may contain oneof the elements Ni, No or Ti. However, it is also possible to use othermetals which are suitable for formation of a metal silicide.

FIG. 1B illustrates a schematic cross-sectional view of a later processstage in this embodiment. In this case, the metal layer 3 is beingirradiated with a laser pulse 4.

The metal layer 3 is irradiated with the laser pulse 4 such that a metalsilicide 6, as is illustrated in the schematic cross-sectional view inFIG. 1C, is formed by thermal action on a boundary surface 5 to the SiCsubstrate.

The formation of the metal silicide is achieved by the introduction ofenergy by absorption of the laser pulse 4 leading to a temperatureincrease above a silicide-formation temperature on the boundary surface5 to the SiC substrate 1. A number of parameters can be set such thatthey can be matched to one another in order to achieve thesilicide-formation temperature by absorption of the laser pulse. Theparameters used include, for example the wavelength of the laser pulse4, the thickness of the layer structure including the layer 2 whichcontains silicon and the metal layer 3, the pulse duration and the pulseenergy. For example, the wavelength of the laser pulse can be chosen tobe in a range from 100 nm to 1000 nm, with the thickness of the layerstructure being in the range from 10 nm to 50 nm, the pulse durationbeing in the range from 20 ns to 2000 ns, and the pulse energy being inthe range from 0.5 J/cm² to 8 J/cm². Because of the multiplicity ofparameter combinations, one example will be mentioned, with a wavelengthof 307 nm (for example excimer laser), a layer structure thickness of 15to 20 nm, a pulse duration of 200 ns and a pulse energy of 3 to 4 J/cm²in conjunction with nickel as the metal layer 3, and polysilicon as thelayer 2 which contains silicon.

FIG. 2A illustrates a schematic cross-sectional view of a process stageat the start of the formation of an electrical contact on an SiCsubstrate, according to a further example. This example differs from theembodiment that has been explained with reference to FIGS. 1A to 1C inone embodiment in that the metal layer 3 is supplied directly to the SiCsubstrate 1, so that there is no layer 2 containing silicon in thisembodiment. The process stages of irradiation with the laser pulse, asillustrated in the schematic cross-sectional views in FIGS. 2B and 2Cfor formation of the metal silicide 6 on the boundary surface 5 to theSiC substrate 1 correspond in principle to the processes illustrated inFIGS. 1B and 1C, and will not be explained in detail once again at thispoint.

FIG. 3A illustrates a schematic cross-sectional view of a process stageat the start of the formation of an electrical contact on the SiCsubstrate 1, according to a further embodiment. In this case, the SiCsubstrate 1 has an exposed SiC substrate surface 7.

In the subsequent process stage illustrated as a schematiccross-sectional view in FIG. 3B, the exposed SiC substrate surface 7 isirradiated with the laser pulse 4.

In this case, the exposed SiC substrate surface 7 is irradiated in sucha way that the SiC substrate 1 loses silicon by thermal action on thesurface 7, and a carbon structure 8 remains. This is illustrated in theschematic cross-sectional view in FIG. 3C. In this embodiment, theenergy must be introduced into the exposed SiC substrate surface 7 suchthat silicon vaporizes from the SiC crystal lattice, and a carbonstructure remains as the carbon structure that forms the electricalcontact. A contact reinforcement structure, for example a Ti/Ni/Ti/Agstack or further layers or layer sequences that are suitable for thispurpose, can be applied to the carbon structure 8 (not illustrated). Inconjunction with this embodiment, it should be noted that, in oneembodiment, short wavelengths of the laser pulse 4 lead to suitableabsorption of the laser energy on the exposed SiC substrate surface 7.If the laser pulse wavelength is increased, it should be remembered thatthe absorption in the vicinity of the surface will decrease, and will beshifted increasingly into the depth of the SiC substrate 1.

A further embodiment will be explained in the following text, in whichthe laser pulse method illustrated in FIGS. 3A to 3C for formation of arear-face contact is integrated in a process for manufacturing asemiconductor component. It should be noted that the embodimentsexplained in conjunction with FIGS. 1A-1C and FIGS. 2A-2C can, ofcourse, also be used to form the rear-face contact.

FIG. 4A illustrates a schematic cross-sectional view of the SiCsubstrate at the start of the manufacturing chain. The SiC substrate 1has a thickness d₁, as well as a front face 9 and a rear face 10.

Processes relating to the manufacture of the semiconductor component arecarried out first, over the front face 9. This is illustrated in ahighly simplified form, in the schematic cross-sectional view in FIG.4B, in the form of a component-specific structure 11 on the front face9. The component-specific structure 11 may include well zones formedwithin the SiC substrate, or else regions formed on the substrate 1,such as a Schottky contact region or an isolation or wiring area. Afterthe formation of the component-specific structure 11 on the front face 9of the SiC substrate 1, the substrate 1 is thinned from the rear face 10starting from the thickness d₁ to a thickness d₂, as is illustrated inthe schematic cross-sectional view in FIG. 4C.

The electrical contact is now formed on the rear face 10 with the aid ofthe method explained in FIGS. 3A to 3C (FIG. 4D). Corresponding to theprocess stages illustrated schematically in FIGS. 3B and 3C, the exposedSiC substrate surface 7 is once again irradiated in this case on therear face 10 of the SiC substrate 1 with the laser pulse 4 such that theSiC substrate 1 loses silicon by thermal action on the rear face 10, anda carbon structure 8 remains.

The carbon structure 8, which forms the conductive contact, isillustrated in the schematic cross-sectional view in FIG. 4E.

Further processes, for example relating to the formation of a contactreinforcement structure, may follow the process stage illustrated inFIG. 4E.

FIG. 5A illustrates a schematic cross-sectional view of an SiC substrate1 at the start of the formation of an electrical contact on the SiCsubstrate 1, according to a further embodiment. In this embodiment, theprocesses carried out are substantially the same as those in theembodiment illustrated in FIGS. 2A to 2C. A metal layer 3 is thus firstof all applied to the SiC substrate 1, see FIG. 5A.

The process stage in the embodiment illustrated in FIG. 5B differs fromthe irradiation of the SiC substrate 1 with the laser pulse 4 accordingto the embodiment illustrated in FIG. 2B in that the laser pulse 4irradiates the metal layer 3 in localized areas. A reticle 12 is used inthe beam path, for this purpose.

As can be seen from the schematic cross-sectional view, as illustratedin FIG. 5C, of the SiC substrate 1 after irradiation with the laserpulse 4, the reticle 12 in the beam path makes it possible to formlocalized areas composed of metal silicide 13. Areas of the metal layer3 as well as the localized areas composed of metal silicide 13 whichform the conductive contact therefore remain on the surface 5 of the SiCsubstrate 1. This embodiment is suitable, for example, for the formationof merged pn-Schottky diodes, which require not only conductive contactareas but also areas with Schottky characteristics on the front face.This embodiment makes it possible to produce such merged pn-Schottkydiodes with only one metallization process, since the metal layer 3 isused not only to form the localized areas composed of metal silicide 13,that is to say the conductive contents, but also the remaining areas,that is to say those which have not been converted, of the metal layer 3as the Schottky contact layer.

Local irradiation of the SiC substrate 1 can be achieved, for example,by scanning, the use of reticles in the beam path, reflector layersand/or contact masks.

FIG. 6 illustrates a schematic illustration of an illumination systemfor local irradiation of the SiC substrate 1. In this case, the laserpulse 4 is produced by a laser source 14, and is passed to the metallayer 3 on the SiC substrate 1 via an imaging system which contains thereticle 12 and additionally has lenses 15 and a deflection mirror 16. Amultiplicity of such localized areas composed of metal silicide 13 canbe produced by scanning the SiC substrate 1.

Although specific embodiments have been illustrated and describedherein, it will be appreciated by those of ordinary skill in the artthat a variety of alternate and/or equivalent implementations may besubstituted for the specific embodiments illustrated and describedwithout departing from the scope of the present invention. Thisapplication is intended to cover any adaptations or variations of thespecific embodiments discussed herein. Therefore, it is intended thatthis invention be limited only by the claims and the equivalentsthereof.

1. A method for producing an integrated circuit including an electricalcontact on an SiC substrate, comprising: providing an SiC substrate;forming a metal layer on one surface of the SiC substrate; andirradiating the metal layer with a laser pulse in order to form a metalsilicide by thermal action, on a boundary surface to the SiC substrate,wherein a layer containing silicon is formed on the surface of the SiCsubstrate before the formation of the metal layer, and the metal layeris produced on the layer containing silicon.
 2. The method of claim 1,comprising wherein the wavelength of the laser pulse is in the rangefrom 100 nm to 1000 nm.
 3. The method of claim 1, comprising wherein thethickness of a layer structure formed on the SiC surface for eradiationwith the laser pulse is in the range from 10 to 50 nm.
 4. The method ofclaim 3, comprising wherein the thickness range is 15 nm to 20 nm. 5.The method of claim 1, comprising wherein the metal layer includes atleast one of the elements nickel, molybdenum, cobalt and titanium.
 6. Amethod for production of an electrical contact on an SiC substratecomprising: providing the SiC substrate with an exposed SiC surface;irridating the exposed SiC surface with a laser pulse such that the SiCsubstrate loses silicon by thermal action on the surface, and a carbonstructure remains; and forming a contact reinforcement structure on thecarbon structure.
 7. The method of claim 6, comprising wherein thewavelength of the laser pulse is in the range from 100 nm to 350 nm. 8.The method of claim 6, comprising choosing the pulse duration to be inthe range from 20 ns to 2000 ns.
 9. The method of claim 6, comprisingchoosing the pulse energy to be in the range from 0.5 J/cm2 to 8 J/cm2.10. The method of claim 6, comprising choosing the pulse energy to be inthe range from 2 J/cm2 to 4 J/cm2.
 11. The method of claim 6, comprisingforming the electrical contact on a front face and/or the rear face ofthe SiC substrate.
 12. A method for production of a semiconductorcomponent comprising: providing an SiC substrate; forming a metal layeron one surface of the SiC substrate; and irradiating the metal layerwith a laser pulse in order to form a metal silicide by thermal action,on a boundary surface to the SiC substrate, wherein a layer containingsilicon is formed on the surface of the SiC substrate before theformation of the metal layer, and the metal layer is produced on thelayer containing silicon. carrying out further processes in order toproduce a semiconductor component.
 13. The method of claim 12,comprising thinning the SiC substrate from the rear face before theformation of an electrical rear-face contact.
 14. The method of claim12, comprising forming the electrical contact on a front face by localirradiation of the metal layer with the laser pulse.
 15. The method ofclaim 14, comprising achieving the local irradiation by scanning the SiCsubstrate, using reticles in the beam path, reflector layers and/orcontact masks.
 16. The method of claim 12, comprising wherein thesemiconductor component is a Schottky diode, and producing a rear-facecontact after the formation of a Schottky junction.
 17. The method ofclaim 12, comprising wherein the semiconductor component is a mergedpn-Schottky diode, and a Schottky metal on a front face of the SiCsubstrate represents the metal layer during local irradiation with thelaser pulse in order to achieve the electrical contact.
 18. The methodof claim 17, comprising: forming a semiconductor structure, includingthe electrical contact.
 19. An integrated circuit comprising: an SiCsubstrate; a layer containing silicon formed on a surface of the SiCsubstrate; and an electrical contact comprising a metal silicide,located on a boundary surface to the SiC substrate.
 20. The integratedcircuit of claim 19, comprising: wherein the metal silicide is formed bythermal action via irradiating a metal layer.
 21. The integrated circuitof claim 19, further comprising: a component structure.